Tobacco use, particularly the practice of cigarette smoking, is the second leading cause of premature death in the world.¹ In recognition of the threat that tobacco use poses to global public health, in May 2003, the member countries of the World Health Organization adopted the Framework Convention on Tobacco Control (FCTC), the first international treaty devoted to health.² To date, the FCTC has been ratified by over 120 countries.

Scientific evidence plays a central role in the FCTC. Its Foreword describes the FCTC as “an evidence-based treaty that reaffirms the right of all people to the highest standard of health”. Its Preamble states that adopting nations are “determined to promote measures of tobacco control based on current and relevant scientific, technical, and economic considerations”. And scientific evidence played a foundational role in the selection and form of the policies that are included in the FCTC.

The FCTC is a seminal event in global health. But the extent to which the FCTC will fulfill its objective of reducing the devastation of the tobacco epidemic will depend on whether the actual policies that parties will formulate and implement are effective. It stands to reason that research could and should also inform this critical implementation phase of the FCTC.

The International Tobacco Control (ITC) Policy Evaluation Project is a multi-country research initiative that was established to build the evidence base for the FCTC and to inform the creation of effective, evidence-based policies under the FCTC. The ITC Project is conducting research to measure the psychosocial and behavioural impact of FCTC policies, primarily those that aim to reduce demand.

The 12 original research articles contained in this Tobacco Control supplement introduce readers to the ITC Project. The lead article by Fong et al³ presents the conceptual model of the ITC Project. The ITC evaluation framework, which is described by Thompson et al,⁴ utilises multiple country controls, a longitudinal design, and a pre-specified, theory-driven conceptual model to test hypotheses about the anticipated effects of given policies. Nine of the 10 empirical articles included in this supplement summarise findings from the ITC Four Country Survey, which was initiated in 2002 and includes data on the smoking practices of random samples of over 2000 adult cigarette smokers in each of four countries—Australia, Canada, the United Kingdom, and the United States. The 10th empirical article reports findings from the ITC Ireland/UK Survey, which was designed to evaluate the 2004 comprehensive smoke-free law in the Republic of Ireland.

The ITC Project has grown so that it now consists of cohort surveys of representative samples of adult smokers in 12 countries—Canada, United States, United Kingdom, Australia, Ireland, Scotland, Thailand, Malaysia, South Korea, China, Mexico, and Uruguay, with additional countries and regions of the globe being added in the near future. All ITC surveys are guided by the same conceptual framework, with survey items that are standardised and consistent across countries. The evaluation research design and methods are identical or similar across countries and are as rigorous as the prevailing conditions allow in each country. Table 1 presents a summary of key findings from the ITC Project to date on tobacco use behaviours and the psychosocial precursors of such behaviours.

A central component of the ITC Project is the first-ever international repository of cigarettes, which is located at the Roswell Park Cancer Institute. The ITC Project Team, in collaboration with the US Centers for Disease Control and Prevention, are conducting studies to examine design features, smoke chemistries, and smoking behaviour (for example, puff topography) in an international context. In the same way as the ITC Surveys are designed to build the evidence base for the demand-reduction policies of the FCTC, research being conducted as part of the international product component of the ITC Project is designed to build the evidence base for tobacco product regulation, which is the focus of Articles 9 and 10 of the FCTC.

The use of parallel national cohort surveys of representative samples of populations across countries that vary along different dimensions (for example, geographic, economic development) yields a research programme of potentially great power not only for measuring the impact of tobacco control policies but also for addressing broader questions about patterns of tobacco use and cessation over time and across countries.

The concept and methods of the ITC Project constitute a research paradigm that could be applied not only to global tobacco control but also to evaluating and understanding policy-based approaches to other important health domains in which public health policies are being implemented or considered, such as in the domain of obesity.